Pulse pressure sensor based on flexible PZT thick-film composite device

In this paper, a flexible diaphragm pressure sensor has been proposed and developed. The piezoelectric lead zirconate titanate (PZT) thick film was used in this sensor as sensing element due to its good piezoelectric property and mechanical flexibility. This kind of PZT film was fabricated recently using tape-casting method. By this process the film thickness can be controlled in the range from tens to hundreds microns, making the novel flexible PZT diaphragm sensor realizable. A sandwiched composite structure of the sensor was designed and fabricated. The properties of the sensor to measure low frequency fluctuating pressures have been investigated experimentally. An experimental setup was designed and constructed to generate pulsing fluid pressure waves and calibrate the sensitivities of sensor samples. The proposed pressure sensor exhibited highly sensitive response to low and quasi-static pressure loading, as well as good flexibility, which is promising in monitoring human blood pressure and respiration.